Convolutely wound container and method of manufacture



Aug. 4, 1959 w. F. WALKER coNvoLuTELY wouNn CONTAINER AND METHOD oF MANUFACTURE:

Filed Jan. 9, 1958 lNvENToR.

A-rraR/vfys United States Patent O CONVOLUTELY WOUND CONTAINER AND METHOD OF MANUFACTURE Willard 1F. Walker, Cleveland, Ohio, assignor to The Cleveland Container Company, Cleveland, Ohio, a corporation of Ohio Application January 9, 1958, Serial No. 708,028

S Claims. (Cl. 229-45) The present invention relates to a wound tubular container and more particularly to the formation of a body structure for a container with a plurality of convolutely wound plies which Iincorporates a pre-cut telescoped par-ting structure whereby the loaded m'shed container may be opened by axial displacement of one portion from another, and `thereafter reclosed by replacing the two parts of the body in a telescoped relation.

Tubular containers are known to the prior art wherein paper like -sheet stock of one type or another is convolutely wound -to form a tubular container body, to the open ends of which suitable caps or closure elements may be applied enclosing material to be packaged therein. Such elements may for example simply be heavy paper or fibrous material formed into shallow cups with cylindrical skirts fitted onto the ends of the body and glued thereto; `or in more rugged containers the end closures may be disc-like sheet metal elements having rim portions carried around the end edge of the body and circumferentially crimped against the container body material. The present invention relates more specifically to `a container of the general class disclosed in the Graves Patent 2,314,338, the Herman Patent 1,961,559 and the Bartlett Patent 934,266, all of tubular form, or the Marshall Patent 2,033,724 of truncated conical form, wherein sheet stock is convolutely wound into the form of the container body, the ystock being ii-rst provided with a longitudinal separation line or cut extending generally in the direction of winding, but comprising two portions relative-ly offset transversely to such direction to provide in two adjacent plies of the final body an axial oiset in a circumferential separation line. This results in a body smic-ture such that one portion may be separated axially from the other as in the disengagement of telescoped elements, whereby the body may be reassembled at the telescoped area. Hence the container as wound inherently includes a removable and replaceable c-ap portion. More specifically this invention improves upon the type of structure and fabrication disclosed in the above named patents by providing on the paper web or blank to be convolutely wound into a container body, and a stripe or coating impeding adhesive bonding of one layer or turn upon the underlying turn at the region of separation from telescoped relation.

The object of such coating, insofar as body fabrication is concerned, is to avoid the need, in the pre-winding application `of adhesive to one side of the web or blank, of keeping an area free of adhesive. Thus one entire side of the web may be coated with the adhesive, with the adhesion preventing coating being applied at the reqquisi-te location on the opposite side, obviating some of the operational inconvenience of prior practice. A further object, insofar as the container itself is concerned, is the provision of structure in which the opening separation of the container body is the more readily and cleanly effected.

The details of container structure and fabrication vfice method are set out hereinafter in full detail with reference to the drawings, wherein:

Fig. l .is aV perspective View of an assembled container fabricated in accordance with the present invention;

Fig. 2 shows the form of the resultant parts obtained upon opening the container of Fig. 1;

Fig. 3 is Ia fragmentary longitudinal cross section of parts corresponding to Fig. 2;

Fig. 4 is la plan view of a unit length of paper web or stock such as may be wound to give the body structure of the container of Figs. 1 3, the showing however being schematic rather than in Lproportion or scale;

Eig. 5 is the obverse of Fig. 4;

Fig. 6 is a fragmentary showing of a modification of the web, viewed as in Fig. 5; and

Fig. 7 is a schematic represent-ation of one manner of winding a web into a container body.

In Fig. l ofthe dra-wings, there appears a finished container (here shown as of cross-section general-ly rectangular with rounded corners) manufactured in accordance with this invention, and comprising a body B convolutely wound from kraft paper web stock, and provided in the usual manner with end closures C, C, shown as metal but usefully of any of the known forms. For clarity of representation, the usual label wrapped about the body is omitted, as well as the label tear-string which would be located at or near 'the line 10. As hereinafter explained in detail, the en-tire body is wound as a unit, closed `at one end, and rthen after lling closed at the remaining open end. rThe structure and manner of fabrication of the body is such that in opening the conrainer, one end of the body B-1 may be disjoined, freed from the remainder of the body B-2, and axially separated from what may be called a latent telescoped relation, as shown in Figs. 2 and 3; yet the two portions of the body may again be telescoped into substantially original relation, so that one part, say B-l, may serve as a replaceable cover or cap for the other.

It will be noted that in the assembled tubular container :of Fig. l, there is an external circumferential dividiug line 10 between the portions of the container body that become resultant upper and lower parts B-l and B-Z upon separation as in Fig. 2. Such line 10 represents an -actual discontinuity in one or more outer turns or layers of wound stock; while within such outer turns, one or more interior turns -or layers are separated by a similar internal circumferential dividing line of discontinuity 11 which is offset from 10 axially or lengthwise of the body. A short joining cut between the lines 10 and 11 is formed in the blank or unit length of web as hereinafter explained.

The result of such offset dividing lines is that upon separation of the container in opening, one resultant part `as B-l has la short projecting neck 13 projecting beyond the shoulder 10a formed by separation at 10; which neck is of course equal in length to the ilange 14 on part B-Z formed by the lsaid outermost layers projecting beyond the internal shoulder 11a resulting by separation of the inner layer or layers at 11. 'I'he neck port-ion then can of course be telescoped with the flange in reassembl-ing the parts as a reclosed container.

To fabricate the body B or such a container, a single elongated rectangular paper blank, or a unit length of a continuous web, corresponding to the convolulte length of the cross section of the desired size container, is rst provided in the pattern `or form of Figs. 4 and 5, which respectively show what upon winding `are the outer and inner sides of the blank. The blank is shown as a conlrainer body of four turns or layers, with two turns involved in the neck 13 and another pair in flange 14. Depending -upon the container strength characteristics required with a given web stock -a different number of turns may be used for the layers forming neck or flange; though of course at least one turn plus some overlap will be required for each in ordinary cases. The spaced vertical dot-dashed lines divide off approximately the web areas involved from right to left in the successively wound layers.

Actually a slight overlapping or excess of four complete turns is provided by the short excess length at the left of the blank.

Spaced inward from one longitudinal edge of the blank, a distance corresponding-to the spacing of line from the top end of the body in Fig. 1, there is a longitudinal slit or cut 10c running over a portion of the blank length corresponding to the two outside turns in the wound container; a second similar cut 11e parallel offset toward the other blank edge from 10c by a distance corresponding to the desired length of neck 13, runs through the rest of the blank length corresponding to the two inner turns, with a short transverse cut 16 connecting 10c and 11e. The structure thus far described is basically that found in common among the aforementioned patents.

Alternatively 10c may be carried into 11C by a generally obliquely disposed curved joining cut as at 16a in Fig; 6.

The entire blank face appearing in Fig. 4 is completely covered with adhesive for winding; and on the obverse side as appears in Fig. 5, a stripe 17 of adhesion preventing coating is applied, beginning near the joining cut 16 (or near 16a in Fig. 6) and running adjacent cut 11C for the length of about a single turn, the third turn in the region between 11C and 10c extended. Where a water solution is used for the adhesive, such stripe may be of a wax insoluble in water and impregnating the web surface, say hot paraffin. With other adhesives, the stripe material will be chosen accordingly.

Thus when a blank is wound onto a rotating mandrel of the-desired cross section (as indicated by the fragmentary dashed outline M in Fig. 7) the adhesive coating bonds each turn to the preceding underlying turn, except at the area of the wax stripe, with the result that the third turn laid down, in the laminating region between lines 10 and 11 in one ply and the following ply respectively, will not bond to the underlying turn. In other words, the inside surface of the region intended to form ange 14 will not be bonded to the outside surface of the region intended to form neck 13. Hence, in the finished container the ready separation of the neck 13 from flange 14 requisite for acceptable simple normal opening of a package is obtained.

For convenience in certain circumstances, the transverse cut y16 may be made to fall short of intersecting both of the offset cuts 10c and 11C, for example to aid in keeping the two longitudinal sections of the blank in adjacent relation in the process; the term bridging cut will be used however to indicate either such a cut or one actually joining 10c and 11C. Also where a particular container application requires incomplete slitting, perforations, or the like along lines corresponding to 10c, llc and 16, the use of the anti-bonding stripe 17, and the fabrication method involving the same are advantageous.

Usually the stripe 17 is at least the width of the offset between 10c and 11C, that is, of the separable telescoped part of the finished container; and in length corresponds to the wound circumference of the interply region to be separated; and preferably, it is restricted within practical operating tolerances to such Width and length, where for repeated opening and closing of the container durability is desired in the neck and flange of the container. However, again in specific container applications, or because of requirements imposed by apparatus handling the body portion in further fabrication or filling or distribution of the container, the stripe may be narrower or shorter than the stated preferred minimums so. that some localized bonding may occur either circumferentially, or say at one spot lengthwise, of the telescoped region, which yet would permit relatively easy deliberate fracture of the bonding to open the container.

Although manual production of tubular containers is unusual, the above disclosed structure and method of forming the body can be applied in such production, for example by cutting a blank to requisite size, forming 10c, 11C and 16, applying the anti-bonding stripe and adhesive, and then winding the blank onto a form or mandrel of proper shape, glue side in or out as desired.

Machine production of containers is of course the more usual. The container is readily produced and its method of fabrication here disclosed carried out by common type convolute winding machines; but with addition, along the web feed path from stock reel to mandrel, of a stripe applying device, and suitable cutting devices. For example, the web may be passed successively through a glue applying station to coat one entire side, then through a wax applying station; then through rotary cutters forming 10c and 11C longitudinally, with a rotating chopper wheel to form 16, before the web reaches the winding mandrel and associated web severing mechanism for winding of the body, with the longitudinal parts of the web on either side of the longitudinal offset cuts 10c, 11e being maintained in adjacent, spatially unseparated relations.

Further, where the machine is to involve a stationary knife past which the web is carried to effect the slitting, such knife may be mounted in such manner, and suitable turning and shifting mechanism provided, that the knife remains at one location relative to the web width say for making 10c, then is camrned to one side for 11C, the blade being rotated slightly from, and then back to normal head-on position during its lateral shift to make say an ogee cut as in Fig. 6 joining the longitudinal cuts. In such case provision likewise would be made to shift the blade back from the position of a completed cut llc of a unit web length for one container to position for beginning the cut 10c on the succeeding unit length.

I claim:

1. In a tubular container, a tubular body of convolutely unitarily wound paper stock having an inner tubular portion of at least one ply, said portion having a circumferential separation line formed therein spaced from one end of the container, a second external tubular portion of at least one ply of stock continuous with that of the inner portion, said second portion having a circumferential separation line offset lengthwise of the container from the first said separation line, the successive plies of the body being'adhesively bonded to each other, one of the stock surfaces having a circumferentially extended anti-bonding coating thereon in the laminating region bounded by one of said lines in one ply and the other of said lines in the next ply, whereby a latent telescoped readily opened joint is provided between the two portions in the region between said lines permitting telescoping reassembly of the body after opening a finished container.

2. In a tubular container, a tubular body of convolutely unitarily wound paper web stock having an inner tubular portion of at least one ply, said portion having a circumferential separation line formed therein spaced from one end of the container, a second external tubular portion of at least one ply of stock continuous with that of the inner portion, said second portion having a circumferential separation line offset lengthwise of the container from the first said separation line, a bridging cut between said separation lines in the web stock in the region where the said inner portion continues into the outer portion, the successive plies of the body being adhesively bonded to each other, one of the stock surfaces having a circumferentially extended anti-bonding coating thereon in the laminating region bounded by one of said lines in one ply and the other of said lines in the next ply whereby a latent telescoped readily opened joint is provided between the two portions in the region between said lines.

3. A method of fabricating a convolutely wound container body of paper stock or like material having more than two turns with successive turns or layers adhesively bonded together, comprising the steps of: forming a blank of the stock with a length corresponding to the convolute length to be found in the desired container; forming lengthwise of the blank from one end a lirst separation line spaced inwardly from the blank edge over a part of the blank length corresponding to approximately the length of at least one turn in the wound container and a second separation line over the rest of the blank length parallel to and offset from the irst separation line, the second line also corresponding in length to at least one turn in the container to be wound; applying a stripe of anti-bonding material to one side of the blank adjacent one of said lines, said stripe in width being about the dimension of the offset between said lines, said stripe beginning at the discontinuity between said lines and having a length approximately the wound circumference of the container; applying an adhesive to the other side of the blank; and convolutely winding the blank length into a container body of the desired tubular form while maintaining the lengthwise areas thereof on opposite sides of the separation lines in spatially unseparated relation.

4. A method of fabricating a convolutely wound container body of paper stock or like material having more than two turns with successive turns or layers adhesively bonded together, said body being axially separable at a latent telescoped joint into two parts, comprising the steps of: forming a blank of the stock with a length corresponding 4to the convolute length to be found in the desired container; forming lengthwise of the blank from one end a rst separation line spaced inwardly from the blank edge over a part of the blank length corresponding to approximately the length of at least one turn in the wound -container and a second separation line over the rest of the blank length parallel to and offset from the first separation line, the second line also corresponding in length to at least one turn in the container to be wound; applying a stripe of anti-bonding material to one side of the blank adjacent and parallel to one of said lines, said stripe in Width being about the dimension of the offset between said lines, said stripe beginning at the discontinity between said lines and having a length approximately the wound circumference of the container; applying an adhesive to the other side of the blank over substantially its entire area; and convolutely winding the blank length into a container body on a mandrel of the desired form while maintaining the lengthwise areas thereof on opposite sides of the separation lines in spatially unseparated relation.

5. A continuous method for fabricating convolutely wound container bodies from a continuous web of paper stock or like material, each body having more than two turns with successive turns or layers adhesively bonded together and being axially separable at a latent telescoped joint into two parts, comprising the steps of: advancing the web to a convolute winding mandrel; applying an adhesive across substantially the entire Width of one side of the advancing web; applying periodically along and parallel to the web length on the other side stripes of antibonding material, said stripes being spaced a distance equal to a unit length of web corresponding to a wound body convolute length; cutting the advancing web to form over part of a unit length a longitudinal slit spaced from one edge of the web and parallel to and oiset therefrom a second slit over the rest of the unit length, said slits each being of length at least that of a single turn in a wound body; said lstripe being in width about the amount of the olset and extending lengthwise from the discontinuity between said slits; winding each unit length of the web on a rotating mandrel, andcutting olf the web from each successively wound body; the lengthwise areas of the web on opposite sides of said slits being maintained in spatially unseparated relation.

References Cited in the le of this patent UNITED STATES PATENTS 934,266 Bartlett Sept. 14, 1909 2,151,202 Guyer Mar. 21, 1939 2,314,338 Graves et al Mar. 23, 1943 2,539,450 Magill Jan. 30, 1951 2,555,380 Stuart et a1 June 5, 1951 2,677,489 Hall et al. May 4, 1954 

